Forum Discussion

becker's avatar
becker
Explorer
Feb 22, 2017

Jake Brake

I have tried posting this message 3 times. The administrator says he does not know why it will not post. He said to resend it. I am retyping everything to see if I included some unsupported characters.

I am on the road. I have a 2008 Monaco Dynasty 425hp Cummins with a Allison 3000 MH 6-Speed World Transmission and Electronic Shifter. Normally on steep downhill grades I can flip the Jake Brake on and it will hold the speed I want, normally 50mph. Now it will not only not hold the speed but the switch feels like it is not connected. I can flip it back and forth and nothing happens. There is a second Jake Brake, HiLo switch, and it works fine, next to the Jake Brake that I use for speed retention and to slow down when I approach a town speed post. I generally only use the second Jake Brake when I am below 40mph and it takes me down to 15mph and then turns me loose.
My question is has anyone else experienced this and is it something I can fix? I appreciate your input. Maybe all of a sudden I am not operating them correctly.

33 Replies

  • Ivylog's avatar
    Ivylog
    Explorer III
    When you try and use the Jake does 2nd show up in the tranny shift pad? If not the switch may not be working... check with a ohm meter and if defective replace with a on/off switch with the same number of contacts. If 2nd shows up then it could be the two wires that connect to the head on your engine... not likely.i

    There is a fuse in the front run box labeled Jake Brake... check it before the switch.
  • There are connections at the switch and solenoids under the valve cover.
    I don't know how you would trouble shoot everything.
    If it was a fuse, I would think nothing would work.
    May, need a expert mechanic for this one.
    Hopefully, someone will jump in with a better answer than mine.
    Pat
  • Don't know anything about Jake Brakes except what they are, but you post shows up fine.